EXPORT, Pa. (AP) -- Police have identified and charged a 16-year-old boy accused of stabbing and slashing 21 fellow students and a security guard at a Pennsylvania high school.
Authorities say Alex Hribal was being charged as an adult following the Wednesday morning attack in Murrysville, 15 miles east of Pittsburgh.
He appeared before Magisterial District Judge Charles Conway and was charged with four counts of attempted homicide and 21 counts of aggravated assault. He was shackled by his hands and feet and was dressed in a hospital gown.
The teenager's family lives in a two-story home with an attached garage in a nice subdivision of large, newer homes there. No one answered the door or phone calls.
The FBI was at the house Wednesday night.
Neighbors say the teenager is the younger of the family's two boys.
Westmoreland County officials say not all of the 20 injured were cut by the knife, some suffered scrapes and cuts in the incident that happened at Franklin Regional High School in Murrysville on Wednesday morning.
Officials say it doesn't appear any students suffered life-threatening injuries. Those injured are between 14 and 17 years old.
The suspect, a male student, was taken into custody and being questioned.
It is unsure what kind of knife was used or what prompted the attack.